diff --git a/utils/conv_codes_gsm.py b/utils/conv_codes_gsm.py
index ec77660..e189985 100644
--- a/utils/conv_codes_gsm.py
+++ b/utils/conv_codes_gsm.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 # -*- coding: utf-8 -*-
 
 from conv_gen import ConvolutionalCode
diff --git a/utils/conv_gen.py b/utils/conv_gen.py
index 06283d8..d2eda15 100644
--- a/utils/conv_gen.py
+++ b/utils/conv_gen.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 mod_license = """
 /*